The present invention is directed toward a roof shingle for solar heat collection and, more particularly, to such a shingle having fluid filled tubes inserted therein.
As prices for oil and electric heating continue to rise, there has been increasing notice given to alternative energy sources. One such source is solar energy. Many existing solar heating systems employ the use of relatively large solar heating panels. See, for example, U.S. Pat. Nos. 4,454,863 and 4,946,512. Installation of these panels is rather complicated and generally requires workers having a substantial amount of training. Additionally, the heating panels are quite expensive. Due to the high cost of installing such a solar heating system many people are deterred from utilizing this vast and readily available energy source. U.S. Pat. No. 4,158,357 suffers from the same deficiencies as the two patents discussed above.
Alternative solar roof systems have been developed. These systems employ the use of interfitting members having some form of heating system incorporated therewith. Again, common drawbacks with these existing solar roof systems are that they are both complicated to install and are relatively expensive. For example, U.S. Pat. No 4,319,437 discloses interlocking roof shingles which form circular openings between a corresponding upper and lower shingle. Fluid conduits are inserted into the circular openings. The conduits extend through adjacent shingles lying in the same course. Positioning adjacent shingles so that the circular openings are properly aligned is rather difficult. Accordingly, skilled workers generally have to be employed for proper installation.
U.S. Pat. No. 4,204,520 discloses roofing tiles with a solar water heating system associated therewith. Each roofing tile has a semicircular groove formed in one surface near the top thereof and a similar groove formed in the opposite surface near the bottom. When two courses are assembled on a roof, a tube is first positioned in the adjacent grooves formed in the tiles that make up the lower course. The adjacent grooves formed in the tiles that make up the upper course are mated with the grooves in the lower course. Therefore, the tube is encompassed by the overlapping portions of the tile. The tube is used to bring heated water to a house located below the roof. A problem with installing the roofing tiles disclosed in this patent is that the semicircular grooves in adjacent tiles must be precisely aligned so that the tubes can be inserted therein. Additionally, there is little room for expansion of the tubes.